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Cheap flights from Toronto Region of Waterloo Intl Airport to Seattle from C$ 216

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 1/6. Fares are subject to change and may not be available on all flights or dates of travel.
YKF — SEA
25 May — 1 Jun1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Region of Waterloo Intl to Seattle

Enter your travel dates to find the best prices.

Cheapest flights from Region of Waterloo Intl to Seattle
Explore the most affordable flight options available from Region of Waterloo Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 25 April 2026.

Wed 3/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Thu 11/67:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 25/4C$ 365
Mon 15/68:40 p.m.
YKF
-
SEA
1 stop25h 05m
WestJet
Wed 24/67:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 20/4C$ 368
Sun 7/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Sun 14/67:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 23/4C$ 371
Thu 4/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Tue 23/67:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 25/4C$ 372
Fri 19/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Wed 24/67:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 24/4C$ 374
Sun 24/58:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Sun 14/67:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 24/4C$ 375
Mon 1/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Wed 10/67:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 23/4C$ 376
Wed 27/58:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Mon 1/67:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 22/4C$ 379
Tue 23/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Tue 30/67:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 25/4C$ 408

Find flight deals from Region of Waterloo Intl to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Region of Waterloo Intl (YKF) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 25 April 2026.

Round-trip from

C$ 365

One-way from

C$ 216

Popular in

June

Cheapest in

February

Average price

C$ 553
WestJet
  • WestJet
  • 3/6-11/6
  • 2 total stops
  • 37h 15m total
  • Toronto to Seattle
Search Deals
WestJet
  • WestJet
  • 1/6
  • 1 total stop
  • 16h 00m total
  • Toronto to Seattle
Search Deals
Highest demand for flights based on searches. 7% potential increase in price (C$ 48 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (C$ 15 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Region of Waterloo Intl to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 629,999 searches. Data last updated 25 April 2026.
Use the filters below to find and compare flights from Toronto Region of Waterloo Intl Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 19/6

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Wed 24/6

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 374

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 5/6

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Tue 9/6

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 376

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Tue 23/6

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Tue 30/6

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 408

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 17/5

8:40 p.m.-6:45 p.m.

1 stop25h 05m

Seattle/Tacoma Intl

Sat 25/7

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 457

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Wed 6/5

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Sun 10/5

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 460

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sat 29/8

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Sun 6/9

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 461

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Mon 3/8

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Thu 6/8

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 461

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Wed 22/7

8:40 p.m.-6:45 p.m.

1 stop25h 05m

Seattle/Tacoma Intl

Sun 26/7

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 464

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 3/9

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Tue 8/9

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 469

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 10/9

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Mon 14/9

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 475

Flights are sorted by cheapest round-trip flights first.

Deals found on 23/4

Showing 1-10 of 23 resultsSorted by cheapest first
1
2
3

Best time to book a flight from Region of Waterloo Intl to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Region of Waterloo Intl with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated 25 April 2026.
Read through reviews of airlines operating flights from Toronto Region of Waterloo Intl Airport to Seattle, such as WestJet. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
WestJet
7.2
Good
3,325 reviews
Check prices

Food

6.2

Entertainment

6.1

Crew

7.9

Boarding

7.4

Comfort

7.0

Overall

7.2

Reviews

1 / 20
6.0
Good

Deb,Jan 2025

YYZ - YYC

Boarding went smoothly, you didn't accept debit card for food on flight
WestJet
7.2
Good
3,325 reviews
WestJet
7.2
Good
3,325 reviews
Check prices

Food

6.2

Entertainment

6.1

Crew

7.9

Boarding

7.4

Comfort

7.0

Overall

7.2

Reviews

1 / 20
6.0
Good

Deb,Jan 2025

YYZ - YYC

Boarding went smoothly, you didn't accept debit card for food on flight

Related info for your journey

Find useful and relevant information for your journey from Region of Waterloo Intl to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Seattle from Toronto Region of Waterloo Intl?

    Seattle/Tacoma Intl (SEA) is the airport you will fly into if you book a flight from Toronto Region of Waterloo Intl to Seattle. You should not have trouble finding flights to Seattle/Tacoma Intl from Toronto Region of Waterloo Intl; the airport handles an average of 0 inbound flights from Toronto Region of Waterloo Intl per day. You should also have plenty of airline options to choose from since 1 airline has flights to the Seattle airport from Toronto Region of Waterloo Intl. It is only a 18.4 km journey from Seattle/Tacoma Intl (SEA) to Seattle’s city centre.

  • How long is the flight from Toronto Region of Waterloo Intl Airport to Seattle?

    Departing from Toronto Region of Waterloo Intl Airport to Seattle will take you 16h. The distance between Toronto Region of Waterloo Intl Airport and Seattle is about 3257 km.

  • What is the cheapest airline to fly from Toronto Region of Waterloo Intl Airport to Seattle round-trip?

    WestJet, at C$ 269, was found to be the cheapest airline from Toronto Region of Waterloo Intl Airport to Seattle..

  • Can I find deals for flights from Region of Waterloo Intl to Seattle that include hotel bookings?

    Yes. In addition to deals on Region of Waterloo Intl to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Region of Waterloo Intl to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Region of Waterloo Intl to Seattle.

  • Can I find deals for business class flights from Region of Waterloo Intl to Seattle?

    Yes. Cheapflights offers flight deals from Region of Waterloo Intl to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Leavenworth
Mukilteo
Kent
Tacoma
Bothell
Cashmere
Olympia
Renton
Marysville
Lynnwood
Kirkland
Tukwila

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Top airline flying from Region of Waterloo Intl to Seattle

Discover the top airline that operate flights from Region of Waterloo Intl to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 629,999 searches. Data last updated 25 April 2026.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapestC$ 269AverageC$ 340FlexibilityNo cancel feeOn-time60%
Search WestJet flights

Fly with Cheapflights

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How does Cheapflights help users find flights from Region of Waterloo Intl to Seattle?

Deals for Region of Waterloo Intl to Seattle flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Region of Waterloo Intl to Seattle?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Region of Waterloo Intl to Seattle.

Can Cheapflights find flights from Region of Waterloo Intl to Seattle with no change fees?

Users can book flights with no change fees policies with our dedicated filters. Book flights from Region of Waterloo Intl to Seattle flexibly with Cheapflights today.

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